This invention relates generally to packaging machinery operable on horizontally fed web material to form, fill and seal individual pouches, each containing a free-flowing granular or powdery product. More particularly, the invention relates to means associated with the filler mechanism whereby the product is deposited or laid down on the web material at precisely defined areas thereof and in a predetermined configuration so as to minimize the amount of web material required for packaging a given amount of product.
In packaging machines of this type a first or bottom web is customarily fed in a horizontal plane beneath a filler mechanism where a predetermined amount of the product is dropped on the web during a dwell in the feed cycle. As the web continues to feed past the filler mechanism a second or top web is introduced into the feed path in overlying relation to the bottom web and the product thereon. Thereafter, as the two webs continue to feed they are sealed together in the areas surrounding the product, thereby forming individual pouches containing the granular product.
When the web material is of a width to accommodate the formation of several pouches simultaneously in several respective lanes, the web material will be sealed together between adjacent pouches in both a longitudinal direction and a transverse direction so as to result in pouches having a rectangular configuration.
In conventional apparatus of this type, when a granular free-flowing product material is dropped or deposited on the product receiving area of the lower web the deposit tends to take on the configuration of a mound or pile of non-uniform height; the maximum height of the mound being located only at its central portion overlying only a relatively small or minor portion of the product receiving area of the bottom web. Thus, in order to effectively enclose a product by the top web when said product has such a mounded configuration, the amount of web material employed must be sufficient to allow for bulging thereof to an extent required for the maximum height of the mound being contained. This amount is considerably more than would be required if product material of the same volume had a configuration which was flatter or more nearly uniform in height over the major portion of the product receiving area of the web material. Furthermore, when granular material is loosely deposited on the web in the form of a mound the precise surface area of the web covered by the mound cannot be accurately predicted due to the random manner in which the free flowing material builds up into a mounded configuration. Thus, in order to provide assurance that none of the material will reach the seal area of the web, the product receiving area of the web needs to be larger than otherwise would be the case.